A new study I coauthored with UCLA’s Dan Losen provides yet another reason to support comprehensive school discipline reform: excess suspensions cost California billions of dollars.

The math is simple: more suspensions mean fewer high school graduates. And reduced graduation rates hurt our economy. That’s because people without high school diplomas typically earn less than graduates, and they are more likely to have health problems and get into trouble with the criminal justice system. That means less tax revenue and increased expenses for health care and incarceration.

Our study finds that reduced high school graduation rates caused by school suspensions *from just a single graduating class* will cost California $2.7 billion. Every school district contributes to this total, and our study, The Hidden Cost of California’s Harsh School Discipline: And the Localized Economic Benefits from Suspending Fewer High School Students, quantifies the total for every California district that enrolls more than 100 10th graders.

The amounts vary widely. For example, over the lifetimes of the 10th grade cohort studied, suspensions in the Los Angeles Unified School District, California’s largest, are estimated to result in $148 million in economic damage. Suspensions in Fresno Unified are estimated to cost $56 million; San Diego Unified will cost $38 million. Suspensions in San Francisco Unified and San Juan Unified, California’s 14th and 15th largest districts respectively, are expected to cost $13 million each.

Despite the findings of our study, Dan and I are confident that California is on the right track. The state has reduced suspension rates in each of the past three years and just designated school discipline as one of seven key state accountability indicators. We hope California will accelerate its work to reduce suspensions, by investing in promising alternative approaches, like Restorative Justice and Positive Behavioral Interventions and Supports, or PBIS.

We also hope that other states will follow California’s lead and make school discipline reform a top priority.